Out on the streets of New York City, it’s the first blizzard of 1958. But a gentler kind of tempest is getting patrons shaken and stirred inside the Bon Soir nightclub, where barkeep-turned-singer Sam Bendrix’s act has grown perilously personal.

Or it would be perilous, anyway, if this were actually 1958 — long before the Stonewall Riots and the subsequent gay-rights movement made the world at least a little safer for someone like Sam.

When Sam’s patter takes on a confessional tone in this La Jolla Playhouse show — staged in an actual bar, Martinis Above Fourth — it’s easy to understand why his pianist Jimmy (Charlie Reuter) tries to wave him off so sternly, warning that the cops could raid the place any minute.

But for a member of Sam's adopted cabaret audience, sitting in this stylish watering hole in the warmly welcoming, proudly gay-centric neighborhood of Hillcrest, it’s a bit harder to really tap into that sense of threat.

Still, that doesn’t take away from what is a warm and persuasive performance by Luke Macfarlane, a star of TV (“Brothers and Sisters”) and Broadway (“The Normal Heart”), as the heartsick romantic Sam. Or from the writing by Keith Bunin, who gives Sam a believably bittersweet back story, and finds graceful ways to fold the show’s classic songs into the character’s saga.

It also helps that Macfarlane cuts a dashing figure, coupled with an appealing voice and a young-Sinatra vibe (if not quite the same purity of pipes). And that he’s backed by a swinging jazz trio led by music director Reuter (a quadruple-threat who’s just about done it all on local stages) and featuring bassist Kevin Cooper and percussionist Danny King, both with sterling theater credits.

Director Mark Rucker’s show, the third in the Playhouse’s “Without Walls” series of site-specific works, puts Sam front-and-center as “the man you come to see when you can’t see the man you really want to see.” In other words, he’s the guy filling in for the Bon Soir’s usual headliner — a big deal after years of slinging martinis behind the bar. (Sam actually incorporates some cocktail-mixing into the act.)

Turns out he’s waiting and hoping for the arrival of the man he really longs to see — society’s disapproval be damned. (One chair is left vacant for the mystery visitor, just in case.)

Introducing himself with tunes such as Cole Porter’s “You’d Be So Nice to Come Home To” and the Bacharach/David hit “The Story of My Life,” Sam tells of his lonely Nebraska upbringing (Jerome Kern’s “The Land Where the Good Songs Go”) and his (mis)adventures in New York (the Gershwins’ “Oh, Lady Be Good!” and “Nice Work If You Can Get It”), as well as of his eventual heartbreak (Kurt Weill's "That's Him," Rodgers & Hammerstein’s “The Gentleman is a Dope”).

Macfarlane, an accomplished cellist, even performs briefly on that instrument (although with a slight hiccup on opening night that had him calling on “Charlie” — instead of Jimmy, the character name — for a do-over).

It’s a measure of the low-key spell this show casts that the upbeat closing number — “Some Other Time,” from the musical “On the Town” — carries a hint of the wistful. It’s a reminder that Sam dreams of some other time to come — one more enlightened than his own.